Reducing GI Illnesses by Extending Municipal Water Service to Private Well Owners

Jacqueline MacDonald Gibson, Ph.D University of North Carolina at Chapel Hill T32ES007018

NIEHS-funded researchers provided new evidence that extending regulated community water service to households currently relying on private wells may decrease the burden of acute gastrointestinal (GI) illness. By combining data on visits to the emergency department for acute GI illness with water quality data, the researchers linked microbial contamination of drinking water from private wells to cases of acute GI illness in North Carolina.

The researchers used 2007-2013 data from North Carolina emergency departments, along with data from community water systems and more than 16,000 water samples from private wells in North Carolina. Approximately 35 percent of the population of North Carolina depends on private wells. The scientists found that 29,400 visits to emergency departments, or 7.3 percent of all emergency visits for acute GI illness, were associated with microbial contamination of drinking water. Of these cases, 99 percent were associated with private well contamination.

The study estimated that the annual cost of emergency department visits attributable to microbes in private wells is $39.9 million in North Carolina. As a result, the authors suggested that extending municipal water service into areas with higher population density that are close to existing infrastructure, while factoring in the potential health benefits, may make municipal service expansion economically feasible. The authors also estimated that extending community water service to just 10 percent of the population currently using private wells in North Carolina could prevent 2,920 annual emergency department visits for acute GI illness.